Table 1.

Extraction method of luteolin.

Abstraction technics	Raw material	Extraction time	Conventional process temperature (°C)	Extraction efficiency(%)/content(mg/g)	Process characteristics	Reference
Impregnation extraction method	Viticis leaves	>72 h	40	9.4 %	Mild, low cost; low extraction efficiency and long extraction time.	[4]
Solvent extraction- Soxhlet extraction	Viticis leaves	2 h	50	14.5 %	Automatic continuous process, less solvent consumption	[4]
ultrasonic assisted method	Lobelia chinensis	30 min	50	0.323 ± 0.014 mg/g	The operation is simple and convenient; the extraction time, temperature and solvent consumption were reduced.	[11]
	Peanut shell	15 min	60	1409 mg/g		[12]
supercritical fluid extraction	–	–	–	6.56 %	High efficiency, not easy to oxidize, pure natural, no chemical pollution.	[14]
microwave-assisted method	Peony pod	>4 h	66	0.151 mg/g	High repeatability, simplified operation, reduced solvent consumption, reduced energy input	[18]
Alkali destruction technology (natural deep eutectic solvent)	Peanut shell	105 min	80	23.33 mg Rutin equivalent/g	It is helpful for flavonoid recovery, high extraction efficiency, and maintaining the antioxidant activity of the extract.	[168]
ultrasound-assisted enzymatic extraction method	celery	30 min	25∼30	9.31 mg/g	The extraction efficiency is high and meets the high performance and economic requirements of the extraction process.	[22]